Schema Component Constraint: length valid restriction

Hi,

"Length valid restriction" says: 
"It is an ·error· if length is among the members of {facets} of {base
type definition} and {value} is not equal to the {value} of the parent
length."

Xerces 2.6.2 and XSV 2.7 seem to handle this constraint differently.

Example:
<xsd:simpleType name="fooType">
  <xsd:restriction>
    <xsd:simpleType>
      <xsd:restriction base="xsd:string">
        <xsd:length value="2"/>
      </xsd:restriction>
    </xsd:simpleType>			
    <xsd:length value="1"/>
  </xsd:restriction>
</xsd:simpleType> 

While XSV does not report an error, Xerces reports:
"(Error) length-valid-restriction: Error for type 'fooType'. The value
of length = '1' must be = the value of that of the base type '2'."

Whom to follow here?

If this is not a bug in the spec, what is the intention of disallowing
to restrict the length of e.g. a string?

Regards,

Kasimier